No. 50.] 49 
beds or veins of magnetic iron ore lie either vertical, or dipping to the 
E. S. E. at an angle corresponding nearly to the dip of the strata."* 
From these facts there can be little doubt that the position and geolo- 
gical relations of this important mineral in the two extremes of the 
State are entirely similar. 
The specular iron ore or red oxide of iron is somev\rhat peculiar in 
its associations. In New-York, this ore is chiefly, though not entirely, 
confined to the counties of St. Lavsrrence, Jeflferson and Franklin, and 
so far as its deposits have been examined, they are found to be con- 
nected with sandstone, which is essentially composed of quartz or 
silica coloured by oxide of iron. This association is also exhibited in 
the ore itself, which frequently contains cavities filled with beautiful 
crystals of quartz, and which sometimes has a flinty or jaspery charac- 
ter. The deposits of this ore, often of vast extent are, moreover, ge- 
nerally, perhaps always, flanked by beds of limestone. 
Nearly corresponding with the occurrence of the specular iron ore at 
the north, is that of the hematitic iron ore, in the southern counties 
of the State, which occurs in extensive beds, and usually lies near the 
junction of the limestone with the talcose slate formation. 
Bog iron ore is almost equally abundant in diflerent parts of the State, 
and does not appear to posess any peculiar geological associations. It 
is evidently formed by the solution and subsequent precipitation of the 
ores found in the older rock formations, and this precipitation has some- 
times taken place at a considerable distance from its original source. 
As in other countries, the ores of lead are not peculiar to any of the 
geological formations, being found here in almost all the series of rocks. 
We may cite as examples, the occurrence of galena in the hornblendic 
gneiss of Rossie, St. Lawrence county ; in the millstone grit of the 
Shawangunk mountains ; at the junction of the limestone and slate rocks, 
in Dutchess and Columbia counties ; in the Trenton hmestone, in 
Lewis county ; and in the calciferous slate, in Monroe county. 
In regard to the associated minerals, there are some which seem to 
be of constant and general occurrence, while others are in part at least in- 
fluenced by the peculiar nature of the rock in which the deposit exists. 
* Geological Reports, 
[Assembly, No. 50.] 7 
